package com.jeecg.p3.goldeneggs.util;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang.StringUtils;


public class EmojiFilter {
	 /**
     * 检测是否有emoji字符
     * @param source
     * @return 一旦含有就抛出
     */
    private static boolean containsEmoji(String source) {
        if (StringUtils.isBlank(source)) {
            return false;
        }
        int len = source.length();
        for (int i = 0; i < len; i++) {
            char codePoint = source.charAt(i);
            if (isEmojiCharacter(codePoint)) {
                //do nothing，判断到了这里表明，确认有表情字符
                return true;
            }
        }
        return false;
    }


    private static boolean isEmojiCharacter(char codePoint) {
        return (codePoint == 0x0) || 
                (codePoint == 0x9) ||                            
                (codePoint == 0xA) ||
                (codePoint == 0xD) ||
                ((codePoint >= 0x20) && (codePoint <= 0xD7FF)) ||
                ((codePoint >= 0xE000) && (codePoint <= 0xFFFD)) ||
                ((codePoint >= 0x10000) && (codePoint <= 0x10FFFF));
    }
    
    /**
     * 过滤emoji 或者 其他非文字类型的字符
     * @param source
     * @return
     */
    public static String filterEmoji(String source) {
    	//update-begin-alex 20161216 for:增加新的过滤表情方法
    	source = filter(source);
    	//update-end-alex 20161216 for:增加新的过滤表情方法
    	//update-begin-gengjiajia 20170104 for:增加新的过滤表情方法
    	source = removeFourChar(source);
    	//update-end-gengjiajia 20170104 for:增加新的过滤表情方法
        if (!containsEmoji(source)) {
            return source;//如果不包含，直接返回
        }
        //到这里铁定包含
        StringBuilder buf = null;
        int len = source.length();
        for (int i = 0; i < len; i++) {
            char codePoint = source.charAt(i);
            if (isEmojiCharacter(codePoint)) {
                if (buf == null) {
                    buf = new StringBuilder(source.length());
                }
                buf.append(codePoint);
            } else {
            }
        }
        
        if (buf == null) {
            return source;//如果没有找到 emoji表情，则返回源字符串
        } else {
            if (buf.length() == len) {//这里的意义在于尽可能少的toString，因为会重新生成字符串
                buf = null;
                return source;
            } else {
                return buf.toString();
            }
        }
    }
    
    /**
     * add-by-alex 20161216 for:增加新的过滤表情方法
     * @param str
     * @return
     */
    private static String filter(String str) {
	    if (str.trim().isEmpty()) {
	        return str;
	    }
	    String pattern = "[\ud83c\udc00-\ud83c\udfff]|[\ud83d\udc00-\ud83d\udfff]|[\u2600-\u27ff]";
	    String reStr = "";
	    Pattern emoji = Pattern.compile(pattern);
	    Matcher emojiMatcher = emoji.matcher(str);
	    str = emojiMatcher.replaceAll(reStr);
	    return str;
	}
    
    /**
     * add-by-gengjiajia 20170104 for:增加新的过滤表情方法
     * @param content
     * @return
     */
    private static String removeFourChar(String content) {
        byte[] conbyte = content.getBytes();
        for (int i = 0; i < conbyte.length; i++) {
            if ((conbyte[i] & 0xF8) == 0xF0) {
                for (int j = 0; j < 4; j++) {                          
                    conbyte[i+j]=0x30;                     
                }  
                i += 3;
            }
        }
        content = new String(conbyte);
        return content.replaceAll("0000", "");
    }
}
